Effects Of Puroindoline A And 1Ax1 On Functional Properties Of Starch And Gluten Protein In Tetraploid Wheat

Wheat end-use quality mainly derives from two interrelated characteristics: milling quality and food-making quality. Puroindoline a(Pina), a main gene which is located on the Ha locus on the short arm of chromosome 5D, determines the grain hardness with Puroindoline b(Pinb). Grain hardness can affect the milling quality directly. PINA protein is mainly combined on the surface of starch and therefore affects the properties of starch when milling. 1Ax1 which is one of high molecular weight glutenin subunits(HMW-GS) can improve gluten strength and affect the food-making quality. To study the common functions of PINA and 1Ax1 on wheat end-use quality and the mechanism, we took full advantage of transgenic lines which are perserved by our lab to research how PINA and 1Ax1 affect the function qualities of starch and gluten protein. The main results are as follows:(1) Laser Particle Size Analyser was used to research the flour particle size of transgenic and control lines. We found that PINA can obviously reduce flour particle size, while 1Ax1 has no obvious effect on flour particle size.(2) Color Difference Meter was used to research flour color change of transgenic and control lines, and we found that PINA can increase flour whiteness, while 1Ax1 has no obvious effect on flour whiteness.(3) Single Kernel Characterization System(SKCS) combined with Near-Infrared Reflectance Spectroscopy was employed to research grain hardness and protein content of transgenic and control lines. Results showed that PINA can significantly reduce grain hardness, while 1Ax1 has no obvious effect on grain hardness. PINA and 1Ax1 both have no significant effect on flour protein content.(4) By using Starch Damage Analyser and flour absorb water ability, we also studied the starch damage of transgenic and control lines, and we found that PINA can obviously reduce starch damage and the water absorbing ability, while 1Ax1 has no obvious effect on starch damage.(5) By using Rapid Viscosity Analyser(RVA), starch pasting properties of transgenic and control lines was investigated, and it was found that PINA can reduce the heat stability of starch pasting properties, while 1Ax1 has no obvious effect on starch pasting properties.(6) By using gluten index analyser to research gluten index of transgenic and control lines, we found that PINA can significantly reduce gluten index and affect the expression of gluten protein.(7) Normal propyl alcohol dissolution method and combined with SDS-PAGE and Western blotting was used to research soluble proteins and insoluble proteins of transgenic and control lines. We found that PINA expressed both in soluble proteins and insoluble proteins, but mainly expressed in soluble proteins and existing by monomer and oligomer.